The present invention relates generally to memory devices and, more particularly, to a memory cell structure not requiring access transistors.
Typical memory cells include a steering element, e.g., one or more transistors, to access each cell. The access transistors, which may also be diodes, provide access for the word lines to the bit lines of the memory cell. That is, the access transistors act as a pass gate to provide access for the word line to the bit line in order to read and write data to a memory cell. With respect to chalcogenide memory cells, the current/voltage required to program the chalcogenide memory cells is relatively high as compared to the operating current/voltage. However, the access transistors may not be able to handle the programming voltages, thereby limiting the current that can be used for programming because a high current may damage the transistors or diodes acting as access transistors for the memory cells.
In light of the foregoing, there is a need for a memory cell structure that enables selective access to the core cells without the need of an access transistor.